To improve the utilization efficiency of nutrients and water and determine the best drip irrigation frequency for long-season tomato cultivation in solar greenhouses, we cultivated tomato grafted seedlings in soil using an integrated water and fertilizer technology: drip irrigation under mulch. Seedlings drip-irrigated with balanced fertilizer (containing 20% N, 20% P2O5, and 20% K2O) and high-K fertilizer (containing 17% N, 8% P2O5, and 30% K2O) once every 12 days were set as control (CK) and that with water once every 12 days as CK1, while other seedling groups, drip-irrigated with a nutrient solution of Yamazaki (1978) formula for tomato, were set as treatments (T1-T4). There were four drip-irrigation frequencies, i.e., once every 2 days (T1), 4 days (T2), 6 days (T3), or 12 days (T4), who received the same total amounts of fertilizer and water over the 12 experimental days. The results showed that, with the decreases of drip irrigation frequency, tomato yield, the accumulation of N, P and K in plant dry matter, the fertilizer partial productivity, and the nutrient utilization rate first increased and then decreased, peaking at the T2 treatment. Compared with CK, under the T2 treatment, plant dry matter accumulation and the accumulation of N, P and K increased by 4.9%, 8.0%, 8.0%, 16.8%, the partial productivity of fertilizer and the utilization efficiency of water increased by 142.8% and 12.2%, the use efficiency of N, P and K was better than CK by 241.4%, 466.6% and 235.9%, respectively, and the tomato yield increased by 12.2%. Under the experimental conditions, drip irrigation with the Yamazaki nutrient solution at a frequency of 4 days could increase the tomato yield, as well as the use efficiency of nutrients and water. Under long-season cultivation, these trends would result in considerable saving of water and fertilizer. Overall, our findings provided a basis for improving the scientific management of water and fertilizers under long-season tomato cultivation in protected facilities.
为提高日光温室长季节栽培番茄的养分和水分利用效率,明确其最佳滴灌施肥制度,本研究以番茄嫁接苗为试材,采用土壤栽培和水肥一体化膜下滴灌方式开展试验。为计算养分利用效率,以常规水溶肥(平衡肥N-P2O5-K2O=20-20-20和高钾肥N-P2O5-K2O=17-8-30)每12 d滴灌1次作为对照(CK),以每12 d滴灌1次清水作为CK1,处理组(T1～T4)均滴灌日本山崎(1978)番茄配方营养液,在确保每12 d灌水施肥总量一致的前提下,分别采用每2 d(T1)、4 d(T2)、6 d(T3)和12 d(T4)滴灌1次的频次进行,研究滴灌频次对长季节栽培番茄产量和养分利用效率的影响。结果表明: 随滴灌频次减少,番茄的产量、干物质和氮磷钾积累量、肥料偏生产力和养分利用效率均呈先升高后降低趋势,在T2处理达到峰值。与CK相比,T2处理番茄植株干物质积累量、氮磷钾积累量分别显著提高4.9%、8.0%、8.0%和16.8%,肥料偏生产力和水分利用效率分别提高142.8%和12.2%,氮磷钾养分利用效率分别提高241.4%、466.6%和235.9%,增产12.2%。本试验条件下,每4 d滴灌1次日本山崎(1978)番茄配方营养液提高番茄养分、水分利用效率和产量的效果最佳,可达到长季节栽培番茄节水节肥的目的。本研究结果可为设施番茄长季节栽培水肥科学管理提供依据。.
Keywords: drip irrigation frequency; long-season cultivation; nutrient accumulation; tomato; water and fertilizer utilization efficiency; yield.